Hydropower has been utilized for thousands of years. Early hydropower projects captured energy from the motion of falling or flowing water and used that energy to power mechanical devices such as flour mills, sawmills, etc. However, once electricity began to be transmitted as a public utility, mechanical hydropower was quickly supplanted by electrical hydropower. In typical installations, large damns are used to impound water which is then directed through turbines to spin generators and produce electricity on a large scale. However, damn-building can create a number of environmental issues. Additionally, some rivers are in locations where building a damn is not feasible. And of course large damns and electrical generation facilities require large capital outlays before any electricity can be generated and sold.
What is needed is an in-stream turbine generator that can generate electricity from flowing water without building a damn or otherwise adversely impacting the environment. An in-stream submersible turbine generator should be easily placed and removed and have a simple, built-in means for raising and lowering the equipment from the flow to perform maintenance, inspection, etc. Furthermore, the submersible turbine generator blades should be shaped so as to utilize the flow efficiently without presenting undue risk to aquatic life.